Abstract [en]

During the development process for new drugs, dose-finding trials have to be conducted and the choice of their design is an important issue. Traditionally, the standard design is a balanced design where equally large groups of patients are treated with different doses of the new drug or with a control. However, it has been identified that other innovative designs might be more efficient: Optimal designs which use non-balanced allocation to dose, and adaptive designs where the allocation to the doses can be changed during the study based on results collected earlier in the study. In a simulation study we will compare efficiencies of balanced non-adaptive, optimal non-adaptive, adaptive two-stage and fully sequential adaptive designs. In all situations considered one can gain from applying optimal design theory. However, when moving from the optimal non-adaptive design to an adaptive design, there are situations where the design is improved and other situations where there is only a minor or no gain. Based on our considered situations, we generalize our observations to answer when an adaptive design is useful.